1. Field of the Invention
The present invention relates to an image-based, patient-specific medical spinal surgery method and a spinal prosthesis for the surgery, and more particularly, to an image-based, patient-specific medical spinal surgery method and a spinal prosthesis for the surgery in which an insertable spinal prosthesis is specified for a shape of each individual patient's spine, is manufactured using a polymer-based material by introducing an image of a patient during surgery, and can be inserted simply during surgery.
2. Description of the Related Art
In treating spine related diseases, an indirect treatment through a physical therapy and a direct treatment to correct and fix a spine by mounting a separate fixing device to a damaged spine are performed.
In other words, the physical therapy is performed when a spinal disease is not serious; however, when a serious disease occurs in a cervical vertebra, a thoracic vertebra, a lumbar vertebra, a sacrum and intervertebral disc, etc., the separate spinal fixing device is used for treatment.
A configuration of the spinal fixing device that is commonly used for a surgery includes a fixing screw that is inserted to a pedicle of a vertebra or a sacral vertebra at a predetermined angle and depth such that a damaged spinal part is corrected to a normal state and fixed in place without moving, a support bar that is positioned on a side of the spinal part, and a fixing cap or a fixing connector for coupling the support bar and the fixing screw.
On the other hand, as shown in FIG. 1, in order to treat the damaged spinal part, the fixing screw is inserted and fixed to the pedicle of the vertebra or the sacral vertebra at an appropriate position and direction, the spinal part is corrected into the normal state by the support bar, and the support bar and the fixing screw are fixed by the fixing cap or the fixing contactor to complete the treatment.
A fixing rod including at least one connecting sliding component that is used for connecting the fixing screw to the fixing rod is inserted to a cylindrical bearing and is fixed by using a tightening means including a small clamp and a tightening screw. The connecting sliding component includes at least one tip that extends away from the cylindrical bearing for the fixing rod in a direction that converges with an axis of the fixing screw. In this manner, the connecting sliding component is temporarily fixed to the spine by being pressed against the spine and the fixing screw is fixed in place by a screw, and lastly, the fixing rod is inserted to the cylindrical bearing in a side direction before fastening the fixing rod by using the small clamp and the fastening screw. The device is designed for spinal transplant on the front.
In a treatment using aforementioned spine fixing device, existing implants are not completely satisfactory. Particularly in the treatment of a spinal bone, the existing implant does not perfectly restore a space between vertebrae, the implant itself becomes an obstacle that hinders the movement of the spine, the implant can be dangerous by being inserted to a vertebral plate, it is difficult to implant the implant, or the implant has a low reliability related to durability of the implant or a transplant fixing unit.
The most serious problem of such a spine fixing device is that the spine fixing device damages the spine.
In a conventional prosthesis for spinal fixation and a surgery using the same, with reference to FIG. 1, the spinal fixation surgery using a screw has the following disadvantages.
First, the prosthesis for correcting the spine is selected based on an image, however the prosthesis is not patient-specific, and a coupling body (e.g., bolt) is nailed into a bone of the spine to attach the spinal prosthesis thereto.
Such invasive spinal treatment may cause a serious problem in that a spinal cord may be damaged and occasionally the bone itself as well.
Also, the spinal prosthesis comprises a relatively large metal structure, by which a patient is repulsed, and the prosthesis that is once adjusted and fixed to the spine is not adjustable such that, when adjustment is required at a later time, an additional surgery is needed.